RU2229043C2 - Internal combustion engine fan drive temperature-sensitive clutch - Google Patents

Abstract

FIELD: transport engineering. SUBSTANCE: invention can be used in cooling systems of automobile and tractor internal combustion engines. Proposed clutch contains temperature-sensitive element, cover, housing installed on drive shaft one radial-thrust bearing, tightener, support bushing with thrust bearing secured on bushing. Support bushing is installed on drive shaft. Temperature-sensitive element is made in form of thin-walled chamber filled with antifreeze with high expansion coefficient and is arranged between cover and tightener. Tightener interacts with thrust bearing, and support bushing contacts with radial-thrust bearing. Transmission of torque to housing and cover of clutch from drive shaft in case of ambient temperature rise is provided owing to transmission of axial forces from chamber through tightener, thrust bearing and support bushing to radial-thrust bearing. When ambient temperature drops, temperature-sensitive element cools and chamber, decreasing in volume, unloads radial-thrust bearing on drive shaft, and rotation of clutch housing decreases. EFFECT: simplified design of clutch, improved efficiency of operation at decrease of ambient temperature. 1 dwg

Description

The present invention relates to mechanical engineering and can be used in cooling systems of automobile and tractor internal combustion engines.

Known technical solutions include the coupling - see fig. 5.9 on page 162 in the book: Design of automobile and tractor engines. Textbook for high schools. AND I. Raikov et al. - M.: Higher School, 1986.

The disadvantages of the known coupling include the complexity of the design.

Closest to the proposed one is a thermosensitive liquid friction coupling of an automobile engine fan drive (AS USSR No. 1176109, class F 16 D 43/20, 1985), comprising a housing and a cover separating their disk, rigidly connected to the drive shaft rotating in the bearing relative to the housing, a partition dividing the inner cavity of the coupling on the working and backup chambers. A viscous fluid circulates through the through-hole in the baffle plate, which is blocked by the valve, which ensures the adhesion of the disk to the housing and clutch cover.

The thermosensitive element, the setting of which at a given response temperature determines the time the valve opens, is made in the form of a biometallic spring.

However, this coupling has a bulky design, requiring its tightness and its operation is not effective enough. This in turn makes the operation of the associated fan also inefficient. Even at low ambient temperatures, the fan has a relatively high speed, which causes an increase in energy costs.

The objective of the proposed technical solution is to simplify the design and increase the efficiency of the coupling at low temperatures.

To solve this problem, the heat-sensitive coupling of the drive of the internal combustion engine fan, containing a heat-sensitive element, a cover, a housing mounted on a drive shaft on a bearing, is additionally equipped with: a clamp, a support sleeve and a thrust bearing fixed on it, the heat-sensitive element is made in the form of a thin-walled chamber filled non-freezing fluid, and is located between the cover and the prepress interacting with the thrust bearing, while the supporting sleeve is fixed to the drive shaft and the contact mating with a bearing on the drive shaft, made angular contact.

The drawing shows the proposed coupling of the fan drive, General view.

The thermosensitive coupling of the fan drive consists of a detachable housing 1 and cover 2, clamp 3, the thermosensitive element 4, the support sleeve 5, the thrust bearing 6 and the angular contact bearing 7.

The heat-sensitive element 4 is made in the form of a thin-walled chamber filled with a non-freezing liquid with a large expansion coefficient and is placed between the cover 2 and the clamp 3. The outer surface of the chamber 4 is made in the form of the internal contact surfaces of the clamp 3 and the cover 2 and is in direct heat transfer contact with the latter .

The prepress 3 interacts with the thrust bearing 6, mounted on the support sleeve 5, in turn, mounted on the drive shaft 8 with a screw 9.

The housing 1 is mounted on an angular contact bearing 7, made with a small contact angle α and connected to the shaft 8 with an interference fit.

The studs 10 are used to secure the fan (not shown) on the housing 1.

The gaps between the chamber 4, the preload 3, the cover 2 and the axial backlash in the bearings 6, 7 are fully selected during assembly of the coupling by the selection of gaskets 11, which is determined by the specified slight torque between the housing 1 and the shaft 8 under normal temperature conditions.

The coupling operates as follows.

During operation of the internal combustion engine, the drive shaft 8 rotates, while it has a slightly higher rotation speed compared to the housing 1 and the cover 2 of the coupling due to some slippage.

With increasing air temperature, heat from the cover 2 is perceived by the camera 4 and the liquid in its cavity begins to expand. In this case, the chamber volume increases and the axial forces from the chamber increase through the clamp 3, the thrust bearing 6 and the support sleeve 5 to the angular contact bearing 7. This increases the torque between the housing 1 and the shaft 8, as a result of which the speed of rotation fixed to the housing the fan increases, approaching the speed of the drive shaft.

When the ambient temperature decreases, the temperature-sensitive element cools, the chamber 4, decreasing in volume, unloads the bearing 7, the rotation of the housing 1 decreases and, therefore, the number of fan revolutions decreases.

Thus, the proposed coupling is simple in design and has high efficiency. In addition, the proposed technical solution simplifies the assembly technology of the coupling, ensures the maintenance of optimal thermal conditions of the engine and low energy costs associated with the operation of the cooling system.

Claims (1)

A heat-sensitive coupling of a drive of an internal combustion engine fan, comprising a heat-sensitive element, a cover, a housing mounted on a drive shaft on a bearing, characterized in that it is additionally equipped with a clamp, a support sleeve and a thrust bearing fixed on it, the heat-sensitive element is made in the form of a thin-walled chamber filled non-freezing fluid, and is located between the cover and the prepress interacting with the thrust bearing, while the supporting sleeve is fixed to the drive shaft and It is mounted with a bearing on a drive shaft made angularly.